1. Field of the Invention
This invention relates generally to an improved propulsion mechanism for use with float tubes commonly used in fishing and, more particularly, to an improved foot fin assembly for propelling the user of such a float tube. Specifically, the present invention relates to an improved foot fin assembly for use in propelling the user of a float tube in a forwardly facing direction while simultaneously permitting the user of such foot fins to walk in shallow water without removing the fin assembly.
2. Description of the Prior Art
In general, users of float tubes for fishing incorporate some type of propulsion devices on their feet in order to assist in moving about the water's surface. Most float tube fins are similar in design to the foot fins used by swimmers and divers. Illustrations of such devices include those shown in U.S. Pat. Nos. 1,745,280, 2,898,611, 3,183,529, 3,268,927, 4,857,024, 4,889,510, 4,929,206, 4,940,437 and 5,108,327 as well as German Patent No. 4020235. Such devices operate by movement of the user's legs and feet in a flutter kick which propels the swimmer or diver in a forward direction. However, when they are utilized by the user of a float tube, they propel the float tube user rearwardly or backwardly relative to the direction the user is facing. This direction is generally opposite the direction the float tube user normally wishes to move when pursuing rising fish or in moving to another spot located in front of him. Moreover, the efficiency of such prior art fins is low so that the use of such devices in traveling any type of a distance when using a float tube is generally very strenuous and tiring.
In addition, these types of fins generally limit normal walking foot movement due to their forward extension portions which create a risk of falling while walking with the fins on. Walking in marginal water to enter or exit a body of water is particularly hazardous, for in addition to the clumsiness of the protruding fins and the restriction of movement and visibility caused by the float tubes, the walker has to overcome the water's resistance on the fins with each step. As a consequence, most users of forward extending fins walk backwards to enter and exit the water, and such backward walking with a bulky float tube in place creates a significant danger of falling and injury to the user.
The process of donning and removing a ring-shaped float tube while wearing such forwardly extending prior art fins is also difficult and hazardous. For example, the bulk and shape of an annular float tube limits movement, necessitating that the fins be attached to the user's feet prior to donning the float tube. In such an instance, with the float tube lying flat on the ground and the fins attached to the user's feet, the user then balances on one foot while stepping over the circumference of the tube with the other foot and inserting the other foot with fin into the leg opening of a float tube seat. Thus straddling the tube, the user then shifts his or her balance to the foot now inside the tube so as to lift the opposite foot with fin over the tube and insert it also into the leg opening of the seat. At this particular point, balancing is especially difficult presenting a danger of falling. The forward extension of such prior art fins, their general configuration and size, and the constriction of the seat of an annular float tube makes it extremely awkward to insert both feet with fins in place into the leg opening of a float tube. Balancing is especially difficult while bending over to maneuver the unwieldy tube into position to facilitate inserting the fin of the second foot into the leg opening.
As the result of such difficulties, several fins have been designed to provide means of forward propulsion by float tube users. Moreover, designs have been provided wherein a single paddle is secured to an existing shoe of a float tube user. Such designs include U.S. Pat. Nos. 1,983,609, 2,395,844 and 4,664,639. Moreover, an unpatented device known as the Paddle Pusher by Fishmaster Manufacturing Co. of Oklahoma City, Okla., provides side paddles to be worn on existing tennis shoes. The design of these type of fins compel the float tube user to assume a forced, unnatural position in the float tube during use. Moreover, these designs are generally inefficient in use relative to a full leg movement of the user of a float tube. For example, the design and construction of a float tube seat typically places a user thereof in the posture of a person seated in a chair with his or her legs and feet extended generally outwardly and forwardly. Use of the fin disclosed in U.S. Pat. No. 4,664,639 requires the user to lean forward against the designed posture of the float tube in order to position his or her legs in a vertical plane to provide sufficient leverage to make use of the device of this particular patent. This is due to the fact that the fin is integrally secured as part of the sole of the shoe or as part of a sleeve that fits over the shoe. In either instance, substantial rearward force from the leg and foot of the float tube user is necessary to move the fin away from the sole of the shoe and into position to create forward user motion. Moreover, this integral flap is by its nature urged toward its closed position against the boot sole. The paddle pusher device also compels the user of a float tube to assume a forced, upright position to move through the water. As a consequence, much of the user's leg motion with these devices is wasted, and such awkward movement within the float tube is inherently dangerous.
U.S. Pat. Nos. 805,525 and 3,081,467 both disclose devices for attachment to the leg of a user to assist in swimming, which devices include plural flaps to assist in propulsion by providing resistance against water movement in one direction. The device illustrated in U.S. Pat. No. 805,525 requires specific movement of the user to open and close the flaps. The device illustrated in U.S. Pat. No. 3,081,467 is adapted to be oriented in a vertically downward position from the toe of a swim flipper for operation and in a vertically upward position in order to permit walking by a swimmer. However, given the nature of a swim flipper, forward walking is very difficult as previously mentioned. Moreover, this device is designed to slip over the foot similar to a swim flipper and designed to help push water away from the foot as the user's leg is extended outwardly thereby pushing the user of a float tube rearwardly as with many prior art devices.
The devices of the above related applications Ser. No. 08/200,751, filed Feb. 23, 1994, now U.S. Pat. No. 5,531,621 and Ser. No. 08/553,770 filed Oct. 23, 1995, the contents of which have been specifically incorporated herein by reference, overcome many of the objections to the prior art devices described above. However, the hinging arrangement of these related inventions can sometimes be a little awkward when moving any one of them from its closed to its operative position. The present invention, however, overcomes all of the aforementioned difficulties of the prior art devices and also improves the ease by which a user of the device can move the device in its reset position for minimum water resistance to its operative position for paddling or to a fixed position for walking in shallow water.